Exploring the efficacy of hormone replacement therapy: a network meta-analysis

Background: Hormone Replacement Therapy (HRT) is a treatment for menopausal conditions. Studies showing benefits of HRT in preventing chronic diseases lead to development of clinical guidelines by the American College of Physicians. This study aims to assess the effectiveness of HRT treatments across cardiometabolic measures including Triglycerides (TG), Follicle-Stimulating Hormone, LDL cholesterol, HDL cholesterol, and Estradiol in menopausal women. Our systematic review is aimed at reporting gaps in scientific knowledge.

Methods: A systematic methodology designed and published in PROSPERO (CRD42022346057) to report network meta-epidemiology analysis was utilised. We used databases by PubMed, Web of Science, ScienceDirect, EMBASE and MEDLINE for studies published between 30th of April 1980-2022. Effects of HRT treatments were explored using a Mixed Treatment Comparison (MTC) model. Fixed and random-effects models were used to address heterogeneity in published studies. Publication bias was assessed and corrected using funnel plots and Egger’s test.

Results: Of 45 eligible studies, our findings indicate a significant statistical heterogeneity between HRTs and reduction of TG, SFH, LDL-C alongside increase of HDL-C and Estradiol among menopausal women. The analysis suggests a lack of direct evidence to support their efficacy in reducing TG, SFH and LDL-C levels or to substantiate HRT’s effectiveness in increasing HDL-C and Estradiol. The results showed no significant publication bias in the meta-analysis of included studies.

Conclusion: Our findings indicate the use of HRT interventions among menopausal women may reduce TG, FSH and LDL-C levels and increase levels of HDL-C and estradiol via oral and oral+ transdermal administration. Our study reaffirms efficacy of HRT in supporting favourable lipid profile among menopausal women whilst highlighting the need for robust and inclusive epidemiology studies and clinical trials that are inclusive to all ethnicities to further develop clinical guidelines and policies.